| 2015 Keio Challenger | |
|---|---|
| Date | 16 November – 22 November |
| Edition | 11th |
| Surface | Hard |
| Location | Yokohama, Japan |
| Champions | |
| Singles | |
 Taro Daniel | |
| Doubles | |
 Sanchai Ratiwatana / Sonchat Ratiwatana | |
The 2015 Keio Challenger is a professional tennis tournament played on hard courts. It is the eleventh edition of the tournament which is part of the 2015 ATP Challenger Tour. It takes place in Yokohama, Japan between November 16 and November 22, 2015.
| Country | Player | Rank1 | Seed |
|---|---|---|---|
 AUS | John Millman | 91 | 1 |
| AUS | Matthew Ebden | 107 | 2 |
| JPN | Tatsuma Ito | 113 | 3 |
| JPN | Go Soeda | 115 | 4 |
| JPN | Taro Daniel | 119 | 5 |
| JPN | Yūichi Sugita | 123 | 6 |
 RUS | Konstantin Kravchuk | 145 | 7 |
| JPN | Yoshihito Nishioka | 146 | 8 |
The following players received wildcards into the singles main draw:
Sora Fukuda Makoto Ochi Masato Shiga Kaito UesugiThe following players received entry from the qualifying draw:
Yusuke Watanuki Kento Takeuchi Yuya Kibi
Peter Kobelt Taro Daniel def. Go Soeda 4–6, 6–3, 6–3 Sanchai Ratiwatana / Sonchat Ratiwatana def. 
Riccardo Ghedin / 
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